I work with a pretty decent chunk of the fortune 500, and I would disagree.
What I've seen is an aversion to the iPads, but there are certain places where they can't keep them out. If wireless is authenticated on AD or PSK, it's very difficult to stop them(though there are a growing number of options). If the executive has the power to override IT policy on approved devices, they have no choice.
For what it's worth, it's commonly referred to as the "Bring Your Own Device (BYOD)" movement or "the iPad problem".
Very few have truly accepted and encouraged iPad use since it's not an enterprise device. If you do have IT sponsorship for it, most companies are having to draw new lines around it rather than simply owning it like they historically did with Blackberries. Examples: you have to pay for your own, it has to be managed by MDM and have wipe privileges, you will have to access all applications through VDI, etc.
That said, enterprises aren't thrilled end users can take them home and sync them with their own iTunes and mess with what IT has built on the tablets. Plus Apple's grip on all aspects of the device don't lend to being controlled by MDM very well.
Enterprises are still looking for a replacement for Blackberry, and Microsoft is looking poised to make a shot. Apple doesn't seem interested in compromising their product to fit into the enterprise market.